Acquisitions - Schedule of Pro Forma Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jul. 01, 2018	Jul. 02, 2017	Jul. 01, 2018	Jul. 02, 2017
Snell Advanced Media
Business Acquisition [Line Items]
Revenues	$ 671,441	$ 634,496	$ 1,285,625	$ 1,213,867
Net income attributable to Belden common stockholders	$ 35,241	$ 11,427	$ 34,169	$ 12,406
Diluted income (loss) per share attributable to Belden common stockholders (in usd per share)	$ 0.86	$ 0.27	$ 0.82	$ 0.29
Thinklogical Holdings LLC
Business Acquisition [Line Items]
Revenues		$ 615,109		$ 1,170,745
Net income attributable to Belden common stockholders		$ 28,250		$ 41,130
Diluted income (loss) per share attributable to Belden common stockholders (in usd per share)		$ 0.66		$ 0.96

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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